NPEX process

After feed acidity adjustment, plutonium and neptunium are recovered in the NPEX process, with high yields and sufficiently low impurity levels to make them suitable for MOX fuel fabrication. 

The raffinate of the NPEX process is fed, without acidity adjustment, to a TRUEX step, where the minor actinides and the REEs are recovered. 

NPEX A process for removing neptunium and plutonium during the processing of nuclear fuel by solvent extraction. The solvent is tributyl phosphate diluted with n-dodecane. Developed by E.R Howitz at the Argonne National Laboratory, Argonne, IL. See also SREX, UREX+. 

UREX [URanium Extraction] A solvent extraction process for extracting uranium and technetium from used nuclear fuel, while rejecting all the transuranic elements. Based on the Purex process, which uses tributyl phosphate in a hydrocarbon mixture, but incorporating acetohydroxamic acid, which complexes the Pu and Np and thereby prevents them from being extracted. Developed by the Westinghouse Savannah River Company in 2003. Associated processes are NPEX, TRUEX, and Cyanex 301. 

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